Laboratory inbred mice are used widely and commonly in biomedical research, but inbred mice do not have a big enough gene pool for the research. In this study, genetic and morphometric analyses were performed to obtain data on the characteristics of a newly developing inbred strain (KWM/Hym) captured from Chuncheon, Korea. All of five Korean wild male mice have the zinc-finger Y (ZfY) gene. Also, all of 19 Korean wild mice used in this analysis have the AKV-type murine leukemia virus gene, indicating that Korean wild mice might be Mus musculus musculus. To identify the genetic polymorphism in KWM/Hym, SNP analysis was performed. In a comparison with 28 SNP markers, there was a considerable difference between KWM/Hym and several inbred strains. The homogeneity between KWM/Hym and the inbred strains was as follows: C57BL/6J (39.3%), BALB/c AJic (42.9%), and DBA/2J (50%). KWM/Hym is most similar to the PWK/PhJ inbred strain (96.4%) derived from wild mice (Czech Republic). To identify the morphometric characteristics of KWM/Hym, the external morphology was measured. The tail ratio of male and female was 79.60±3.09 and 73.55±6.14%, respectively. KWM/Hym has short and agouti-colored hairs and its belly is white with golden hair. Taking these results together, KWM/Hym, a newly developing inbred mouse originated from wild mouse, might be use as new genetic resources to overcome the limitations of the current laboratory mice.
Animals ; Female ; Gangwon-do* ; Gene Pool ; Hair ; Humans ; Korea* ; Leukemia Virus, Murine ; Male ; Mice* ; Polymorphism, Genetic ; Tail

Circling mouse (C57BL/6J-cir/cir) deleted the transmembrane inner ear (Tmie) gene is an animal model for human non-syndromic recessive deafness, DFNB6. In circling mouse, hair cells in the cochlea have degenerated and hair bundles have become irregularity as time goes on. Tmie protein carries out a function of the mechanoelectrical transduction channel in cochlear hair cells. Myosin7a (MYO7A) protein has key roles in development of the cochlear hair bundles as well as in the function of cochlear hair cells. To find whether Tmie protein interacts with MYO7A proteins in the cochlea postnatal developmental stage, we investigated expression of the MYO7A proteins in the cochlear hair cells of circling mice by western blot analysis and whole mount immunofluorescence at postnatal day 5 (P5). The expression of MYO7A showed statistically significant increase in the cochlea of C57BL/6J-+/cir and C57BL/6J-cir/cir mice than that of C57BL/6J-+/+ mice. The MYO7A intensity of the cochlear hair cells also increased in C57BL/6J-+/cir and C57BL/6J-cir/cir mice compared with those of C57BL/6J-+/+ mice. Taken together, the results indicate that Tmie protein may have an important role with MYO7A protein in the development and maintenance of the stereociliary bundles during postnatal developmental stage of the cochlea.
Animals ; Blotting, Western ; Cochlea ; Deafness ; Ear, Inner ; Fluorescent Antibody Technique ; Hair ; Hair Cells, Auditory* ; Humans ; Mice* ; Models, Animal

Background: With advance of next-generation sequencing (NGS) techniques, the need for mitochondrial DNA analysis is increasing not only in the forensic area, but also in medical fields. Methods: Two commercial programs, Converge Software (CS) and Torrent Variant Caller for variant calling of NGS data, were compared with a considerable amount of sequence data of 50 samples with a homogeneous ethnicity. Results: About 2,300 variants were identified and the two programs showed about 90% of consistency. CS, a dedicated analysis program for mitochondrial DNA, showed some advantages for forensic use. By additional visual inspection, several causes of discrepancy in variant calling results were identified. Application of different notation rules for mitochondrial sequence and the minor allele frequency close to detection threshold were the two most significant reasons. Conclusion With prospective improvement of each program, researchers and practitioners should be aware of characteristics of the analysis program they use and prepare their own strategies to determine variants.

OBJECTIVE: To assess the learning curve of novice residents in diagnosing acute appendicitis using abdominal computed tomography (CT) scans. METHODS: This prospective observational study was conducted within a 4-month period from March 1 to June 30, 2015. After CT scans for right lower quadrant pain or similar acute abdomen were evaluated, postgraduate year 1 (PGY-1) residents completed an interpretation checklist. The primary outcome was evaluation of the learning curve for competent CT scan interpretation under suspicion of acute appendicitis. Secondary outcomes were cumulative numbers of accurate abdominal CT interpretations regardless of initial clinical impression and training period. RESULTS: PGY-1 residents recorded a total of 230 interpretation checklists. There were 53, 51, 46, 44, and 36 checklists recorded by individual residents and 92, 92, 91, 91, and 61 respective training days in the emergency department, excluding rotation periods in other departments. After 16 to 20 interpretations of abdominal CT scans performed under suspicion of acute appendicitis, the residents could diagnose acute appendicitis with more than 95% accuracy. Overall, the sensitivity and specificity for diagnosing acute appendicitis were 97% (95% confidence interval, 94 to 100) and 83% (95% confidence interval, 80 to 87), respectively. After 61 to 80 abdominal CT interpretations regardless of suspicion of acute appendicitis and after 41 to 50 days in training, PGY-1 emergency department residents could diagnose acute appendicitis with more than 95% accuracy. CONCLUSION: PGY-1 residents require 16 to 20 checklist interpretations to acquire acceptable abdominal CT interpretation. After performing 61 to 80 CT scans regardless of suspicion of acute appendicitis, they could diagnose acute appendicitis with acceptable accuracy.
Abdomen, Acute ; Appendicitis* ; Checklist ; Diagnosis* ; Emergency Service, Hospital ; Learning Curve* ; Learning* ; Observational Study* ; Prospective Studies* ; Sensitivity and Specificity ; Tomography, X-Ray Computed

Background: Inbred mice have several advantages, including genetic similarity to humans, a well-established gene manipulation system, and strong tolerance to inbreeding. However, inbred mice derived from a limited genetic pool have a small genetic diversity. Thus, the development of new inbred strains from wild mice is needed to overcome this limitation. Hence, in this study, we used a new strain of inbred mice called KWM/Hym. We sequenced the Mx1 gene to elucidate the genetic diversities of KWM/Hym mice and observed the biological alterations of the Mx1 protein upon influenza A infection. Results: The Mx1 gene in KWM/Hym mice had 2, 4, and 38 nucleotide substitutions compared to those in the Mx1 gene in A2G, CAST/EiJ, and Mus spretus mice, respectively. Moreover, the Mx1 protein in KWM/Hym mice had 2 and 25 amino acid substitutions compared to those in the Mx1 protein in CAST/EiJ and M. spretus mice, respectively. To elucidate the function of the Mx1 protein, we inoculated the influenza A virus (A/WSN/1933) in KWM/Hym mice. Nine days after infection, all infected KWM/Hym mice survived without any weight loss. Four days after infection, the lungs of the infected KWM/Hym mice showed mild alveolitis and loss of bronchiolar epithelium; however, the pulmonary viral titers of the infected KWM/Hym mice were significantly lower than that in the infected BALB/c mice (2.17 × plaqueforming units mL −1 ). Conclusions Our results demonstrate that the KWM/Hym mice are resistant to influenza A virus infection. Further, these mice can be used as a model organism to understand the mechanism of influenza A virus susceptibility.

Components of silk including silk fibroin have long been used as anti-diabetic remedies in oriental medicine. However, detailed mechanisms underlying these anti-diabetic effects remain unclear. In this study, we examined the anti-diabetic activity of silk fibroin hydrolysate (SFH) in C57BL/KsJ-db/db (db/db) mice, a well-known animal model of non-insulin dependent diabetes mellitus. When the db/db mice were administered SFH in drinking water for 6 weeks, hyperglycemia in the animals gradually disappeared and the level of glycosylated hemoglobin decreased, indicating that SFH plays important role in reducing the symptoms of diabetes. In addition, SFH-treated db/db mice exhibited improved glucose tolerance with increased plasma insulin levels. Immunohistochemical and morphological analyses showed that SFH up-regulated insulin production by increasing pancreatic beta cell mass in the mice. In summary, our results suggest that SFH exerts anti-diabetic effects by increasing pancreatic beta cell mass in a non-insulin dependent diabetes mellitus mouse model.
Animals ; Diabetes Mellitus ; Drinking Water ; Fibroins ; Glucose ; Hemoglobin A, Glycosylated ; Hyperglycemia ; Insulin ; Insulin-Secreting Cells ; Medicine, East Asian Traditional ; Mice ; Models, Animal ; Plasma ; Silk

Purpose: Hypoxaemia is a significant adverse event during endoscopic retrograde cholangiopancreatography (ERCP) under monitored anaesthesia care (MAC); however, no model has been developed to predict hypoxaemia. We aimed to develop and compare logistic regression (LR) and machine learning (ML) models to predict hypoxaemia during ERCP under MAC. Materials and Methods: We collected patient data from our institutional ERCP database. The study population was randomly divided into training and test sets (7:3). Models were fit to training data and evaluated on unseen test data. The training set was further split into k-fold (k=5) for tuning hyperparameters, such as feature selection and early stopping. Models were trained over k loops; the i-th fold was set aside as a validation set in the i-th loop. Model performance was measured using area under the curve (AUC). Results: We identified 6114 cases of ERCP under MAC, with a total hypoxaemia rate of 5.9%. The LR model was established by combining eight variables and had a test AUC of 0.693. The ML and LR models were evaluated on 30 independent data splits. The average test AUC for LR was 0.7230, which improved to 0.7336 by adding eight more variables with an l 1 regularisation-based selection technique and ensembling the LRs and gradient boosting algorithm (GBM). The high-risk group was discriminated using the GBM ensemble model, with a sensitivity and specificity of 63.6% and 72.2%, respectively. Conclusion We established GBM ensemble model and LR model for risk prediction, which demonstrated good potential for preventing hypoxaemia during ERCP under MAC.